What disasters have rain brought to mankind in history?

Rainstorm: generally refers to rain with heavy precipitation intensity, which is stipulated by China's meteorological department:

1 and 1 hour rainfall 16 mm above rain;

Rain with a rainfall of 50 mm or more within 24 hours.

The characteristics of this rainstorm are "concentration" and "high intensity". As soon as it happens, it will pour down, and in a short time, it will cause water accumulation in depressions, sudden increase in runoff and skyrocketing river water. This is a severe and disastrous weather. Because of the obvious monsoon in China, the annual rainfall is mostly concentrated in May-September, so the next period of time is designated as the "flood season". The "flood season" is the most tense and critical period for the meteorological department's forecasting service.

China also has many disasters caused by heavy rain, such as:

1, July 2004 10, Beijing was hit by a torrential rain, which caused most roads in the city to accumulate water and traffic was almost completely paralyzed.

2. In the Yinhu Cave Scenic Area in Fangshan District, the highway was washed into a rocky ditch. The rainstorm that lasted for nearly 6 hours completely destroyed a 2-kilometer-long road surface in Yinhu Cave Scenic Area in Fangshan District. The roadbed was also washed into a rocky ditch by the rain. The water is more than half a meter deep and the current is fast. The transportation of five coal mines in three villages on the mountain was completely interrupted.

3. In July, 2004, the continuous rainstorm caused by typhoon led to mudslides and flash floods in central and southern Taiwan Province Province, which aggravated the local disaster. 2 1 person died, 9 people were missing, and the total loss of agricultural disasters exceeded NT$ 2.3 billion. The loss of fishery facilities exceeded NT$ 70 million. Floods cut off power for 265,438+000 households in central and southern China. After emergency repair, by the middle of the night on the 4th, there were still13,000 households without electricity, among which more than 8,000 households could not carry out emergency repair due to road collapse and bridge fracture. In terms of water supply, 200,000 households failed to resume normal water supply. The flood caused 94 road collapses in the south-central region, and 50 roads were not opened for emergency repair. Due to the damage of subgrade, some sections of the railway stopped.

4. The rain disaster caused serious losses to Yili Prefecture. On July1August-20, 2004, a sudden rainstorm (rainfall 103mm) occurred in Yili Prefecture, causing 220,000 people to be affected. The affected area of crops is 32,449 hectares, with no harvest area15,465,438 hectares and death scale. 13,508 households with 25,423 dangerous houses and 67,246 houses leaking rain. * * Caused economic losses of 63.85 million yuan (including agricultural losses of 9.42 million yuan). 1 1 to1October 3, the rain lasted for three days, and the residential houses generally leaked rain. According to statistics, 10308 households with 4 1233 people were affected, 3,344 houses collapsed, and15,430 houses leaked rain and cracks turned into 368 dilapidated houses collapsed, resulting in economic losses of 187 10000 yuan.

5. In September 2004, a rainstorm occurred in the east and north of Sichuan Province, resulting in 19 deaths, 2 1 missing and 40 serious injuries. The 24-hour rainfall reached 253.2 mm, and the water level of the river rose sharply, causing flash floods and many mudslides and landslides. At present, there are 65438 people in 60 townships in the county.

6. In Guangdong Province, the high water level in Xijiang River, Beijiang River and Pearl River Delta will last for several days, and heavy rain will soak rivers and lakes for many days. After drainage, the flood caused 54 deaths and a loss of 2.4 billion yuan in Guangdong.

7. In April 2004, the urban area, Hengyang County and Hengnan County of Hengyang City, Hunan Province were suddenly hit by heavy rain. The maximum wind force reaches 9, and the maximum wind speed reaches 23 m/s. A century-old tree was uprooted, tiles were flying about, and hail was half the size of a fist. Street billboards were rolled up by the storm and fell to the ground. The rainstorm disaster has caused 7 deaths, 207 injuries and 2,430 houses collapsed. 700 farmers are homeless. All 22 high-voltage power lines in the disaster area were paralyzed, and there was a power outage throughout Hengyang County. The affected area of crops reached 1 106 hectares, including 366.9 hectares, and the affected population was about 400,000.

8. Since mid-June 2005, the southern part of Taiwan Province Province has been hit by heavy rainfall, resulting in agricultural losses of more than 2 1.77 billion yuan, setting a record for agricultural rain losses in Taiwan Province Province. ...

More rain has also brought many landslides:

1.In August 2005, it rained continuously in Hong Kong. According to reports, there were at least 24 floods, 20 landslides and 30 tree collapses. Traffic on Lantau Island has been severely hampered by landslides. Due to the continuous heavy rain, there have been many landslides on Lantau Island. Two major roads on Lantau Island were closed due to landslides. More than 200 tourists were caught in heavy rain after visiting the Tiantan Buddha in Angping, Lantau Island.

2. The Indian financial city Mumbai was hit by a tropical storm for two consecutive days, and more than 60 people died from landslides and floods caused by the storm. Most of the dead in Mumbai were residents of shanty towns on the hillside, and many of them were buried alive with their families. Heavy rain caused traffic jams in some places, and power supply and communication were interrupted. Of Mumbai12 million people, 60% live in slums. Schools in Mumbai were closed and the campus was used as a temporary shelter for homeless victims.

3. From June, 5438 to February, 2003, the death toll caused by heavy rain and landslides in the central and southern Philippines increased to at least 15 1, and many people were still missing. Persistent bad weather, blocked roads, power supply and external communication, made the rescue work very difficult, and many victims dug with their bare hands to search for missing family members.

Less rain will also cause drought;

Drought: Drought is an agricultural meteorological disaster, which leads to insufficient soil moisture and destroys crop water balance. It is also the most serious meteorological disaster in China. If drought is accompanied by destructive human activities, it will cause a series of more serious environmental deterioration problems, which are mainly manifested in three aspects in China: first, drought causes the continuous reduction of water resources and the increasingly prominent water crisis; Second, due to drought, the water level of the lake is reduced, and the water surface is reduced or even dried up; Third, drought has led to the obvious expansion of desertified land.

In 1 and 2003, most parts of Africa suffered from a once-in-a-century drought. About 65438+500 million people in 36 countries are threatened by hunger. In 1.983 alone, 1.6 million people died of hunger and malnutrition-related diseases. In 2008-06, the adoption rate of riding a donkey to chase after running was 23.6%. Good (1) and bad (1).

The rain in the poet's eyes is poetic, but the rain in nature is endless. It can wash away bridges, flood and destroy crops, and bring disaster to mankind. Next, please talk about different situations of rain from a scientific point of view.

1. Tell an example of rain flooding.

In ancient times, Dayu controlled water and Bangladesh was flooded.

2. List strange phenomena related to rain: plum rain, Yu Qian, mud rain, acid rain, etc. Talk about the causes of their formation and the disasters they bring to mankind.

(1) Meiyu:

From the middle and late June to the early summer of the first half of July, there is often a continuous rainy period from the middle and lower reaches of the Yangtze River (or Jianghuai Basin) to southern Japan, with frequent precipitation processes and frequent heavy rains. At this time, it is the mature period of plums in Jiangnan, so it is called "Meiyu". The ancient poem "It rains at home in Huangmei season, and frogs are everywhere in the grass pond" vividly describes the natural scene in the local rainy season.

(2) Yu Qian:

(1) phenomenon:

When it comes to the materials published in Yuqian People's Daily, it is stated that "one day in 1994, Gorky in the Soviet Union suddenly began to rain with a large number of ancient copper coins, which people call the rain copper coin rain". In China, there are many such examples. According to Ren Fang in the Southern and Northern Dynasties, in his book Shuo Wen Jie Zi, "In a week, it rained all day in Xianyang."

"In the Han Dynasty, people in Yingchuan spent a lot of money in the rain." According to "Song Shi Wu Xing", "In July of the second year of Shaoxing, the world was qian yu, or it flowed out of the sarcophagus." "Collection of Ming History" also recorded this: "On June 9, Chenghua Ding You was caught in the rain in the capital, and he often received money in the rain.

Besides, we also know that there is golden rain. "Bamboo Chronicle" said: "In the summer and June of the eighth year of Yu Xia, Xiayi went to gold." Later, Ren Fang also wrote: "As the ancients said, Yu Xia prospered in Xia Zhishi and spent three days in gold. The ancient poem says: it is safe for the sky to rain golden rain, making it as low as earth. Yes. " He wrote in the Difference Notes.

There are also abundant grains. Ren Fang said: "When King Huan of Wu was in power, it rained in Jinling. The poor people had food, but the rich people didn't have rain." According to him, it seems that God really distinguishes between the rich and the poor. This is a sideline, of course. Liu's Bieyuan in Song Dynasty.

He also said, "Zhang Jun, a native of Liangzhou, was born in Gong Yan. After nine years of rain in Wuwei, he stewed it clearly and planted it well." There is a drop of rice in the grain. For example, Cui Bao's Notes on Ancient and Modern Times in the Jin Dynasty said: "In three years, it rained in Guigong and Yangzhai." Xiaomi also has a drop. Cui Bao also wrote: "In the fourth year of Yuankang in Xuan Di, it rained in Chang 'an. It rains black millet in July. Similarly, "History of the Yuan Dynasty and Five Elements" contains: "In October of the eleventh year of the Yuan Dynasty, rice was planted in the northeast of Quzhou; Shao Wuyu black millet, such as reed; There is rain and black millet in Xinzhou, and there are many counties and cities where people eat. "There is rain and millet. Cui Bao said, "Four years after the founding of the People's Republic of China, the rain fell." "Three years of rain millet in Emperor Xuandi Festival, and rain millet in Chang 'an." Of course there is rain and wheat. Zhang Hua's "Natural History" in the Jin Dynasty contains: "When Emperor Wu of the Han Dynasty, it rained wheat in Yangguangjun."

If you only read the books mentioned above, you can't find all kinds of other interesting stories about rain. In fact, twenty.

There are countless materials in the five history notes. Then open the History of Han Dynasty and Records of Five Elements, which read: "In August of the second year in Yong Guang, Yuan Di, it rained grass, but the leaves were cemented as big as a projectile." This can probably be called grass rain.

In addition, Cui Bao also said: "Han Emperor Yonghe Zhong, Chang 'an Yu Mian, are all white." He also said: "Xuan Di Yuankang was born in Nanyang for four years.

Jade bucket. "History of Song Dynasty" and "Records of Five Elements" also contain: "In June of the second year of Yuanfeng, Yudu was in Zhongzhou; In July, beans were planted in Nanbin County. " These examples of cotton rain and bean rain can show that when it rains, there are still many things that can fall with the rain, not just what we are talking about.

② reasons

So, how to explain this phenomenon? Are these supernatural phenomena? Obviously not. These phenomena are actually caused by cyclones. Cyclones, also known as return air, have long been known by the ancients.

Li, an astronomer in the Tang Dynasty, was quoted in the book "A glimpse of the sky" in the Ming Dynasty as saying: "The return air suddenly rises and turns like a horn, turning upwards, rising from top to bottom, or grinding the ground, which is always called return air." When the return air blows, sand and stones fly, rising from the ground and soaring into the sky. So things on the ground are often blown into the sky.

In fact, the reason for these phenomena is very simple.

When we go to the countryside, we often see a whirlwind rolling up sand and turning it into a yellow dragon. It is said that if people are in the center of this tornado, it will be very dangerous. Even the birds in the sky can't escape when they meet this tornado. Therefore, "History of the Song Dynasty Five Elements" said: "In December of the second year of Qingyuan, in Jin 'e Township, Wuxian County, millions of copper coins flew by themselves. "Of course, it was blown away by the whirlwind." The money in the treasury flew about. At that time, all the houses of Nantai people had money, and all the tiles were erected. Each piece was made of bamboo, or a dozen or twenty pieces, all of which were money. "Chang 'an Hakka Dialect by Jiang Yikui in the Ming Dynasty also wrote," The old tower in Zhuozhou was in Sanggan River, and the tower collapsed in the first year of Jiajing, which contained ancient money. "These records are the same.